Notice how most of these people are below the age of 30? With a slim chance at opportunities a lot more people are gonna snap. There is a ton of pressure and little chance of success. Most of these people are people who fail and want a way out. Why Canada doesn't have the problem? A lot less of the bullshit that is going on here. When you live somewhere where failure is unacceptable you'll get people who fail and can't deal with it and do this shit. As for Norway? I can't say, not to up to date on Norway. They do have pretty similar characteristics as the U.S though.
Im all for having fun, showing your tits and getting fucked up on a river float but it can be done without being a pig.